FXUS66 KHNX 090519
AFDHNX

Area Forecast Discussion
National Weather Service Hanford CA
1019 PM PDT Wed Jul 8 2026


&&

.KEY MESSAGES...

1. Lake Wind Advisory for San Luis Reservoir and Lake Isabella 
through 11 PM PDT Thursday, July 9. Beware of unsettled waters.

2. Slow but steady warmup this week, with widespread Moderate Heat
Risk by the weekend and isolated areas of Major Heat Risk. 

3. Hot, dry, and windy conditions will create elevated fire 
risk, particularly in eastern Kern and Tulare Counties. 

4. Increased chance for Sierra Nevada thunderstorms late this 
weekend into next week with monsoonal moisture pushing into our
region.

5. Practice safety around lakes, rivers, and streams, as water 
is still running cold.

&&

.DISCUSSION...
High pressure sliding westward over southern and central
California from the Four Corners region is contributing to a
gradual warming trend that will become more evident in the late
week and weekend. Thursday brings a 40 to 50 percent probability
for maximum temperatures to exceed 100 degrees in the San
Joaquin Valley, especially for the southern and western areas.
However, as the high continues to build, these probabilities
jump to 80 to 90 percent for the valley areas on Friday and
Saturday. For the remainder of the region, temperatures will be
around five degrees above season averages going into the
weekend. 

A tighter pressure gradient on the north side of the high will
result in gustier conditions especially for the areas in the lee
of area mountain ranges and the typical wind prone areas
including San Luis Reservoir, Lake Isabella, and the Mojave
Desert Slopes. Lake Wind Advisories remain in effect for the
lake areas listed until 11 PM Thursday. West winds 15 to 20 mph
with gusts up to 35 mph are expected for San Luis Reservoir and
west winds 15 to 25 mph with gusts to 40 mph for Lake Isabella. 

A drying trend will coincide with the triple-digit heat, with
minimum relative humidity on Thursday expected between 12 and 
20 percent for the San Joaquin Valley, and between 5 and 10
percent for the higher elevations of the Sierra Nevada and the
Kern County Desert. These low humidity values will slowly
improve through the next few days before a dramatic increase due
to monsoonal moisture pushing into the region from the 
southeast. 

Between Sunday and Monday, the aforementioned high pressure
system will slide eastward over the Great Basin, prompting the
upper level flow to shift to the southeast. This will bring
warm, moist air to the region, maintaining temperatures in the
low 100s for the lower elevations, but resulting in chances for
showers and thunderstorms over the Sierra Nevada. Ensemble
guidance from the National Blend of Models expresses a 50 to 60
percent probability for at least one-tenth of an inch over 24
hours ending 5 AM Tuesday for the Sierra between Fresno and
Tulare Counties. There is also a 20 to 30 percent probability
for thunderstorms across this area each day Monday through at
least Wednesday as there is little deviation in the synoptic
pattern through the middle of next week. 

&&


.AVIATION... 

VFR conditions expected across the area for the next 24 hours.
40 to 50 percent chance for wind gusts to exceed 20 kts at TAF
sites in the San Joaquin Valley between 04Z and 07Z Thu. 

&&

.FIRE WEATHER...
Rising temperatures into this weekend will create drier
conditions across the region, with minimum relative humidity
values at 12 to 20 percent across the San Joaquin Valley and
between 5 and 10 percent for the Sierra Nevada and Kern County
Desert Thursday. A gradual improvement will occur over the 
following days, but largely remain within 5 percent of 
Thursday's minimums. Stronger wind gusts approaching 40 mph in 
the Mojave Desert Slopes will cause elevated fire weather 
conditions when combined with the low RH values. In the late 
weekend, an influx of monsoonal moisture will bring showers and 
thunderstorms to the Sierra Nevada, with chances currently 
sitting at 20 to 30 percent each day beginning Monday. Outside 
of the mountain areas, temperatures will remain above 100 
degrees as flow tracks into the region from the southeast. 

&&

.AIR QUALITY ISSUES...
None.


&&

.CERTAINTY...

The level of certainty for days 1 and 2 is high.
The level of certainty for days 3 through 7 is medium.

Certainty levels include low...medium...and high. Please visit
www.weather.gov/hnx/certainty.html for additional information
and/or to provide feedback.

&&

.HNX WATCHES/WARNINGS/ADVISORIES...
Lake Wind Advisory until 11 PM PDT Thursday for CAZ300-332.
&&

$$

public/aviation...McCoy

weather.gov/hanford